/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2002-2003, Network Appliance, Inc. All rights reserved.
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 *
 * MODULE: dapl_ep_disconnect.c
 *
 * PURPOSE: Endpoint management
 * Description: Interfaces in this file are completely described in
 *              the DAPL 1.1 API, Chapter 6, section 5
 *
 * $Id: dapl_ep_disconnect.c,v 1.15 2003/07/30 18:13:37 hobie16 Exp $
 */

#include "dapl.h"
#include "dapl_ia_util.h"
#include "dapl_ep_util.h"
#include "dapl_evd_util.h"
#include "dapl_adapter_util.h"

/*
 * dapl_ep_disconnect
 *
 * DAPL Requirements Version xxx, 6.5.9
 *
 * Terminate a connection.
 *
 * Input:
 *      ep_handle
 *      disconnect_flags
 *
 * Output:
 *      None
 *
 * Returns:
 *      DAT_SUCCESS
 *      DAT_INSUFFICIENT_RESOURCES
 *      DAT_INVALID_PARAMETER
 */
DAT_RETURN
dapl_ep_disconnect(
        IN DAT_EP_HANDLE ep_handle,
        IN DAT_CLOSE_FLAGS disconnect_flags)
{
        DAPL_EP *ep_ptr;
        DAT_RETURN dat_status;

        dapl_dbg_log(DAPL_DBG_TYPE_API | DAPL_DBG_TYPE_CM,
            "dapl_ep_disconnect (%p, %x)\n", ep_handle, disconnect_flags);

        ep_ptr = (DAPL_EP *) ep_handle;

        /*
         * Verify parameter & state
         */
        if (DAPL_BAD_HANDLE(ep_ptr, DAPL_MAGIC_EP)) {
                dat_status = DAT_ERROR(DAT_INVALID_HANDLE,
                    DAT_INVALID_HANDLE_EP);
                goto bail;
        }

        /*
         * Do the verification of parameters and the state change
         * atomically.
         */
        dapl_os_lock(&ep_ptr->header.lock);

        /*
         * Check the EP state to ensure we are queiscent. Note that
         * we may get called in UNCONNECTED state in order to remove
         * RECV requests from the queue prior to destroying an EP.
         * See the states in the spec at 6.5.1 Endpont Lifecycle
         */

        if (ep_ptr->param.ep_state != DAT_EP_STATE_CONNECTED &&
            ep_ptr->param.ep_state != DAT_EP_STATE_DISCONNECTED &&
            ep_ptr->param.ep_state != DAT_EP_STATE_ACTIVE_CONNECTION_PENDING &&
            ep_ptr->param.ep_state != DAT_EP_STATE_COMPLETION_PENDING &&
            ep_ptr->param.ep_state != DAT_EP_STATE_DISCONNECT_PENDING) {
                dapl_os_unlock(&ep_ptr->header.lock);
                dat_status = DAT_ERROR(DAT_INVALID_STATE,
                    dapls_ep_state_subtype(ep_ptr));
                goto bail;
        }

        if (ep_ptr->param.ep_state == DAT_EP_STATE_DISCONNECTED) {
                /*
                 * Calling disconnect when DISCONNECTED is a NOOP, just return
                 * good.
                 */
                dapl_os_unlock(&ep_ptr->header.lock);
                dat_status = DAT_SUCCESS;
                goto bail;
        }

        if (ep_ptr->param.ep_state == DAT_EP_STATE_DISCONNECT_PENDING &&
            disconnect_flags != DAT_CLOSE_ABRUPT_FLAG) {
                /*
                 * If in state DISCONNECT_PENDING then this must be an
                 * ABRUPT disconnect
                 */
                dapl_os_unlock(&ep_ptr->header.lock);
                dat_status = DAT_ERROR(DAT_INVALID_PARAMETER, DAT_INVALID_ARG2);
                goto bail;
        }

        if (ep_ptr->param.ep_state == DAT_EP_STATE_ACTIVE_CONNECTION_PENDING ||
            ep_ptr->param.ep_state == DAT_EP_STATE_COMPLETION_PENDING) {
                /*
                 * transition ep_state to DISCONNECT_PENDING
                 */
                ep_ptr->param.ep_state  = DAT_EP_STATE_DISCONNECT_PENDING;
                dapl_os_unlock(&ep_ptr->header.lock);
                dapls_ib_disconnect_clean(ep_ptr, DAT_TRUE,
                    IB_CME_CONNECTION_REQUEST_PENDING);

                /*
                 * we do not have to post an event here.
                 * the CM will generate one.
                 */
                dat_status = DAT_SUCCESS;
                goto bail;
        }

        /*
         * Transition the EP state to DISCONNECT_PENDING if we are
         * CONNECTED. Otherwise we do not get a disconnect event and will be
         * stuck in DISCONNECT_PENDING.
         *
         * If the user specifies a graceful disconnect, the underlying
         * provider should complete all DTOs before disconnecting; in IB
         * terms, this means setting the QP state to SQD before completing
         * the disconnect state transitions.
         */
        if (ep_ptr->param.ep_state == DAT_EP_STATE_CONNECTED) {
                ep_ptr->param.ep_state = DAT_EP_STATE_DISCONNECT_PENDING;
        }
        dapl_os_unlock(&ep_ptr->header.lock);
        dat_status = dapls_ib_disconnect(ep_ptr, disconnect_flags);

bail:
        dapl_dbg_log(DAPL_DBG_TYPE_RTN | DAPL_DBG_TYPE_CM,
            "dapl_ep_disconnect () returns 0x%x\n", dat_status);

        return (dat_status);
}